MARCIA TALITA AMORIM MARQUES
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Resumo IPEN-doc 23292 Atmospheric stability using Doppler Wind Lidar profiler: a Case Study in Florianópolis Island2016 - SANTOS, P.A.A.; SAKAGAMI, Y.; HAAS, R.; PASSOS, J.C.; TAVES, F.F.; NASSIF, F.; MOREIRA, A.; MOREIRA, G.A.; MARQUES, M.T.A.; BEU, C.; LANDULFO, E.The effects of atmospheric stability can be important for many wind energy applications. This work aims to investigate the atmospheric stability using two Doppler wind lidar profilers based on a simple method that analyses how the wind shear variates with height. The experiment was carried on Florianopolis Island, located in the south coast of Brazil. The dataset covered a period from December 2014 to February 2015. The Windcube08 lidar has a range from 40m to 500m and the Windcube70 lidar was setup to range from 100m to 1000m. Both lidars recorded a 10min average wind speed with a vertical resolution of 20m. In addition, a 3D sonic anemometer measured turbulent fluxes at 20Hz. The method evaluated the variation of wind shear with height and was associated with the stability classes based on Obukhov Length. The wind speed of the two lidars was compared at 100m, 200m, 300m, 400m and 500m. This comparison showed an excellent agreement, with values better than R2=0.996 and RMSE=0.15 m/s. The results of wind profile indicated an unique condition at night, where were consistently observed convective wind profiles from 40m to 120m and stratified flow above 120m. Then, the presented method was adjusted to consider wind profile heights from 120m to 300m. The analysis of the atmospheric stability also presented a good agreement when comparing both lidars. The Very stable, stable and near stable conditions represented 41,2% (Windcube08) and 27,6% (Windcube70). On the other hand, the unstable condition was dominated by a very unstable condition with 21% and 38,7%, respectively. The neutral condition was the most frequent with 36,8% and 32,2%, respectively. The results of atmospheric stability classes diverged between the two lidars from 5h to 10h UTC, because of differences on wind speed average of around -0.8 m/s from 100m to 200m. In conclusion, the site presented specific conditions, which showed the challenges to propose an universal method to estimate the atmospheric stability using only doppler wind lidar data. However, the method achieved good agreement when comparing the wind profile with the atmospheric stability classes.Resumo IPEN-doc 23291 Nocturnal jet observational study over Sao Paulo city with wind Lidar2016 - BEU, CASSIA M.L.; MARQUES, MARCIA T.A.; LANDULFO, EDUARDOSao Paulo is the biggest city of a dense Metropolitan Region with more 38 municipalities. The statistic government agency (IBGE) estimates that more than 20 million of inhabitants live in the Metropolitan Area. Just for Sao Paulo City, the population is more than 11 million of inhabitants and 7 million vehicles, in according to Detran (the traffic agency). Such density is a challenge for managing the quality air control and several studies have been carried out to understand the pollution dispersion over Sao Paulo Metropolitan Region (SPMR). Lapat (a Sao Paulo University team that studies pollution) have been developed important researches in this topic and some results are available in its site (http://www.lapat.iag.usp.br/index.html). One important result is that car emissions have high impact over the atmospheric pollution. Although that and others initiatives, many questions remain unanswered and the observational aspects represents a huge barrier as have been highlighted in several works. The data absence in the PBL (Planetary Boundary Layer) over SPMR was emphasized in a recent work dealing with LES modelling of the Nocturnal Jet (NJ). Therefore, the PBL observational features are an important contribution to research development of SPRM pollution dispersion field. In this sense, this work presents some aspects of the NJ observed over Sao Paulo City with a wind lidar for three months period (December-2015, January-2016 and February-2016) and expect to contribute to SPMR dispersion researches.Artigo IPEN-doc 22797 Estimation of turbulence production by nocturnal low-level jets in Sao Paulo (Brazil)2016 - BEU, CASSIA M.L.; MARQUES, MARCIA T.A.; NAKAEMA, WALTER M.; SAKAGAMI, YOSHIAKI; SANTOS, PEDRO A.A.; MOREIRA, A.C. de C.A.; LANDULFO, EDUARDOTwo Doppler lidars were recently used to collect data from the planetary boundary layer (PBL) in Sao Paulo city (23º32’S, 46 º38’W). The measurement campaign was carried out from December-2015 to February-2016, during the summer, which is the rainy season. Although Sao Paulo is the main city of a huge metropolitan region with more than 11 million of inhabitants and 7 millions of vehicles, according to the government agencies, the lack of PBL observational data is still a limitation for the atmospheric dispersion studies. Therefore, this work should contribute to the comprehension of PBL mechanisms and also for future atmospheric modeling studies. The data revealed that the nocturnal low-level jets (LLJs) frequently occurred along those 3 months, but its height is highly variable, from 100 m up to 650 m. It was also seen that the nocturnal LLJs can extend for several hours, right before the sunset until sunrise. This work aims to investigate the turbulence production by the nocturnal LLJs and its influence into the stable boundary layer (SBL).